1. Technical Field
This invention generally relates to a vacuum canister for use with central vacuum systems. More particularly, the invention relates to a vacuum canister having a mounting bracket that holds various components. Specifically, the invention relates to a vacuum canister having a mounting bracket that is adapted to accept multiple size vacuum pump assemblies, has a mechanism for supporting the system's main circuit board, and has a mechanism for rapidly and easily securing and releasing the system's filter from the filter support.
2. Background Information
Central vacuum cleaner systems are common in newer homes and other buildings. These systems provide a convenient and easy way for periodically vacuuming the floors or rugs in the various rooms of a building and they eliminate the need for moving cumbersome hand-held units from room-to room.
Central vacuum systems typically include a vacuum canister, a light, portable hose, a range of vacuum cleaner attachments, a network of conduits installed in the walls and floors of the building and a number of wall-mounted receptacles. The vacuum canister is usually positioned in an out-of-the-way location in the building, such as the basement, utility room or garage.
Vacuum canisters include an electric vacuum pump assembly that is used to create the suction to draw dust-laden air through the portable vacuum hose and the rest of the central vacuum system. Canisters also include a motor for driving the pump, a filter for collecting dust entrained in the airstream, a device for collecting the entrained dust and a mechanism for circulating cleaned air back into the building.
The portable hose used with these types of systems is typically a flexible hose that includes an elongated rigid tube at one end and an end fitting at the other end. Various cleaning attachments are connectable to the elongated rigid tube and the end fitting is connectable to the conduit system through the wall receptacles.
The wall receptacles include an intake valve covered by an airtight flap or pivotable valve plate to prevent air from being unintentionally drawn into the conduit system. This maintains the vacuum state within the central vacuum system. Air enters the system only through the wall receptacle to which the portable hose is attached. The vacuum pump assembly motor is automatically turned on when the portable hose is attached to the wall receptacle.
While prior art devices have functioned in a reasonably satisfactory way, the systems have been limited inasmuch as a user has had to preselect the capacity system they need for their home or building. Smaller buildings require a smaller vacuum pump assembly to drive the system than do larger buildings. In the past, vacuum canisters have accepted only one size of vacuum pump assembly—a smaller version or a larger version. Additionally, previously known mechanisms for securing filters to vacuum systems have been difficult to use. Filters have been provided with a hole through which a long threaded rod has had to be inserted, with the user having to thread the rod into the hole with the filter blocking the user's vision. Furthermore, previously known systems have used a funnel for directing dust from the dust-collection chamber into a collection bin for disposal. The funnels have merely rested on the top of the collection bins. Consequently, every time the user wishes to empty the bin, the funnel has to be placed on a surface in the building so that the bin could be emptied. When the funnel is put down on the surface, loose dust that has remained on the funnel tends to drop on the surface, thereby creating an immediate need for vacuuming the same up once the system is reassembled.
Various types of vacuum canisters have been devised to separate dirt from the dirt-laden air vacuumed from the rooms of a building. One common design utilizes a cylindrical filter similar to an elongate version of those used in automobiles for years. The design has a pleated filter body capped by respective rubber end rings. The filter is disposed in a lower dirt-collecting portion of the vacuum canister to filter our dirt particles prior to passing through a suction pump driven by an electric motor. Alternatively, a filter bag may be placed over a cylindrical ribbed structure to filter the dirt-laden air prior to entering the vacuum pump. The pleated filter provides more surface area than the filter bag and consequently lasts longer before it becomes plugged up with dirt. With either of these filters, dirt-laden air typically enters the dirt-collecting portion of the canister through an air inlet that is disposed so as to allow the incoming air to perpendicularly strike the air filter. This may cause premature clogging of the filter with dirt since both the larger and smaller dust particles may be retained by the air filter. A more desirable situation is for the larger dust particles to fall immediately to the bottom of the canister and into the collection bin.
Another common design for vacuum canisters, is the cyclonic separator in which the air inlet is disposed tangentially to the filter so that the air travels along a curved interior surface of a cylindrical separation chamber. A curved “skirt” hangs down from an upper end of the separation chamber so as to aid in directing the incoming dirt-laden air between an interior surface of the separation chamber and an exterior surface of the skirt. The dirt-laden air flows downwardly in a spiral motion within the separation chamber and, as it does this, the larger particles drop out of the moving air for collection. Once the flow of air reaches a bottom portion of the separation chamber, the airflow changes direction and spirals upwardly within a vortex created by the downwardly spiraling air. The flow of air is then directed from the separation chamber to an air filter that filters out the remaining dust and dirt from the airflow prior to the air entering the vacuum pump. The cyclonic separator extends the life of the air filter by preventing premature clogging with particles that are large enough to be removed effectively by the cyclonic action.
Various patented devices have been designed in an attempt to alleviate the shortcomings of prior art devices. For example, in U.S. Pat. No. 4,721,516, issued on Jan. 26, 1988 to Barsacq there is disclosed a central vacuum canister unit which includes three interconnected sections which form an integral vacuum canister. The vacuum canister utilizes water to filter the dirt-laden air. A top section of the canister contains a suction turbine, a motor and an exhaust outlet for clean air. A center section contains air baffles, a perforated circular conduit below the air baffles for dispersing the water, an angled inlet conduit for dust-laden air, and a water level sensor. A bottom section contains a water outlet, a flexible sleeve valve, an outlet end of the angled inlet conduit from the center section, a water reservoir filled with water to a level above the outlet end of the inlet conduit—even with the water outlet, and a drain plug. The dirt-laden air bubbles through water in the reservoir, which water is automatically flushed by electronic control circuitry coordinating a filling and evacuation sequence of the reservoir.
In U.S. Pat. No. 4,944,780, issued on Jul. 31, 1990 to Usmani, there is disclosed a vacuum canister comprising four detachable subassemblies and a detachable filter assembly. A first subassembly comprises a vacuum motor and exhaust housing having an inlet opening at one end for admitting dirt-laden air that is drawn into the housing by the vacuum motor. A second subassembly comprises a housing adapted to be secured to a wall to support the vacuum canister as installed. This housing houses a vacuum cleaner inlet. A cyclonic flow of air is created in the housing during operation of the vacuum motor. A third subassembly comprises a dirt collecting housing for receiving and holding dirt particles released by the cyclonic air flow. A fourth subassembly comprises a base plate adapted to be secured in a fixed relationship with the first subassembly and the second subassembly. A hole through the base plate permits a flow of air between the first and second subassemblies. A bracket, adapted to removably secure an air filter, includes a device that engages the base plate such that the air filter is secured thereon in proper filtering relation between the first and second subassemblies.
There is therefore a need in the art for providing a mechanism for providing a convenient, cost effective, safe vacuum unit having the features of being able to selectively mount vacuum pump assemblies and circuit boards of different types, of having a quick and easy mechanism for attaching and detaching the system filter and for preventing the need to lay the dust-laden funnel in the vicinity of the vacuum canister when the user is emptying the collection bin.